Sensor signal processing system and method

ABSTRACT

A method includes generating movement signals indicative of sensed movement of a powered system in one or more directions and generating fluid level signals indicative of a sensed amount of fluid in the powered system. The method also includes, with one or more processors, receiving the movement signals and the fluid level signals from one or more accelerometers and a fluid level sensor, wherein the one or more processors also configured to filter at least some of the movement signals based on a speed at which the powered system operates. The method also includes, with a first antenna of the sensor assembly, wirelessly communicating one or more of the movement signals or the amount of fluid to a remote location.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/365,980, filed 1 Dec. 2016, which claims priority to U.S. ProvisionalApplication No. 62/269,315, filed 18 Dec. 2015, each of which isincorporated herein by reference in its entirety. This application isrelated to U.S. patent application Ser. No. 14/421,245 (filed 12 Feb.2015), Ser. No. 14/866,320 (filed 25 Sep. 2015), and Ser. No. 14/869,038(filed 29 Sep. 2015), the entire disclosures of which are incorporatedherein by reference.

FIELD

The subject matter described herein relates to systems and methods thatuse process information (e.g., data) provided by sensors, such assensors disposed onboard vehicles.

BACKGROUND

Various systems can include sensors for monitoring characteristics ofthe systems and/or surroundings of the systems. For example, vehiclesystems, stationary power systems, etc., can include several sensorsmonitoring the same or different characteristics. These sensors canmonitor vibrations, temperatures, states, or the like, of the systems inorder to track operation of the systems, identify unsafe conditions,determine when maintenance or repair of the systems are needed, or toachieve other objectives. The data provided by the sensors may be usedfor one or more purposes to control operation and/or monitor health ofthe vehicles.

BRIEF DESCRIPTION

In one embodiment, a sensor assembly includes one or more accelerometersconfigured to generate movement signals indicative of sensed movement ofa powered system in one or more directions, a fluid level sensorconfigured to generate fluid level signals indicative of a sensed amountof fluid in the powered system, and one or more processors configured toreceive the movement signals and the fluid level signals from the one ormore accelerometers and the fluid level sensor. The one or moreprocessors also are configured to one or more of filter at least some ofthe movement signals based on a speed at which the powered systemoperates or calculate one or more of statistical measure, a fast Fouriertransform (FFT), or a discrete Fourier transform (DFT) of the movementsignals. The assembly also includes a first antenna configured towirelessly communicate the one or more of the movement signals, theamount of fluid, the statistical measure, the FFT, or the DFT to aremote location.

In one embodiment, a system includes a sensor configured to generatevibration signals indicative of senses vibrations of a vehicle, and oneor more processors configured to one or more of: filter at least some ofthe vibration signals based on a speed at which a motor of the vehicleoperates and communicate the vibration signals that are not filtered outof the sensor, or calculate one or more of statistical measure, a fastFourier transform (FFT), or a discrete Fourier transform (DFT) of thevibration signals and communicate the one or more of the statisticalmeasure, the FFT, or DFT out of the sensor.

In one embodiment, a method includes generating vibration signalsrepresentative of sensed vibrations of a vehicle using a sensor, and oneor more of: filtering at least some of the vibration signals that aresensed based on a speed at which a motor and wheels of the vehicleoperates and communicating the vibration signals that are not filteredout of the sensor, or calculating one or more of statistical measure, afast Fourier transform (FFT), or a discrete Fourier transform (DFT) ofthe vibration signals and communicating the one or more of thestatistical measure, the FFT, or DFT out of the sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

The inventive subject matter described herein will be better understoodfrom reading the following description of non-limiting embodiments, withreference to the attached drawings, wherein below:

FIG. 1 illustrates a sensor system onboard a vehicle system according toone embodiment;

FIG. 2 illustrates one embodiment of a propulsion system in the vehicleshown in FIG. 1;

FIG. 3 illustrates a circuit diagram of a sensor shown in FIG. 1according to one embodiment;

FIG. 4 illustrates a frequency signature of a propulsion systemaccording to one example; and

FIG. 5 illustrates a flowchart of one embodiment of a method forsensing, processing, and/or communicating data representative ofcharacteristics of a powered system.

DETAILED DESCRIPTION

Reference will be made below in detail to example embodiments of theinventive subject matter, examples of which are illustrated in theaccompanying drawings. Wherever possible, the same reference numeralsused throughout the drawings refer to the same or like parts. Althoughembodiments of the inventive subject matter are described with respectto vehicle systems such as trains, locomotives, and other rail vehicles,embodiments of the inventive subject matter are also applicable for usewith vehicles generally, such as off-highway vehicles (e.g., vehiclesthat are not designed or permitted to travel on public roadways),agricultural vehicles, and/or transportation vehicles (e.g.,automobiles, trucks, etc.), each of which may include a vehicle consist.A vehicle system may be formed from two or more vehicles thatcommunicate with each other to coordinate travel of the vehicle system,but that are not mechanically linked with each other. For example, avehicle system may include two or more vehicles that wirelesslycommunicate with each other so that the different vehicles may changethe respective speeds, tractive efforts, braking efforts, and the like,to cause the separate vehicles to travel together as a convoy or othergroup along the same route. Optionally, one or more embodiments of thesystems and methods described herein may be used with othernon-vehicular systems, such as stationary powered systems.

FIG. 1 illustrates a sensor system 100 onboard a vehicle system 102according to one embodiment. The vehicle system 102 shown in FIG. 1includes a single vehicle 104, but optionally may represent two or morevehicles that travel together along a route. The vehicles may bemechanically coupled with each other to travel together as a vehicleconsist or may be mechanically decoupled but communicate with each otherto coordinate movements of the vehicles and travel together as a convoyalong the route. The vehicle can represent a propulsion-generatingvehicle, such as a locomotive, automobile, marine vessel, or the like.Optionally, the vehicle can represent a non-propulsion-generatingvehicle, such as a rail car, trailer, barge, or the like.

The components of the vehicle and/or sensor system may be operablyconnected by one or more wired and/or wireless connections. The vehicleincludes a control system 106 that operates to control operations of thevehicle and/or vehicle system. The control system 106 can include orrepresent hardware circuitry that includes and/or is connected with oneor more processors (e.g., microprocessors, field programmable gatearrays, integrated circuits, or other electronic logic-based devices).The control system 106 may receive signals from an input device 108,such as one or more throttles, pedals, buttons, switches, microphones,touchscreen, keyboards, or the like. An operator of the vehicle mayactuate the input device to control operations, such as movement, of thevehicle via the control system.

In response to receiving the input from the operator, the control systemmay communicate signals to one or more components of the vehicle orvehicle system to implement the input. For example, the vehicle mayinclude propulsion systems 110 having traction motors, gear boxes, axles122, wheels 112, etc., that generate tractive effort or torque to rotatethe axles and wheels of the vehicle to propel the vehicle system. Thecontrol system can communicate signals to the traction motors to controlthe torque generated by the traction motors, the speed at which thetraction motors operate, etc., to control movement of the axles andwheels of the vehicle or vehicle system. In another example, the controlsystem can communicate signals to brakes or other components to controloperations of the vehicle or vehicle system.

Although not shown in FIG. 1, the vehicle can include an output devicethat provides output to an operator of the vehicle or the vehiclesystem, to an off-board location, or to one or more other components ofthe vehicle or vehicle system. The output device can represent adisplay, a touchscreen, a speaker, a wireless transceiver, etc. Theoutput device can receive signals from the control system that directthe output device to present the output to the operator or otherlocation. A communication system 116 represents hardware circuitry thatcommunicates data signals with one or more locations or systems locatedoff-board the vehicle. The communication system can include transceivingcircuitry, such as one or more antennas 114, routers, modems, and thelike, for communicating data signals.

The sensor system includes several sensors 116. The sensors canrepresent a variety of devices that monitor characteristics of thevehicle system and/or the environment around the vehicle system. Forexample, the sensors may include temperature sensors (e.g., sensors thatoutput data representative of temperatures of the vehicles and/orenvironment, such as hot box detectors, infrared cameras, etc.),vibration sensors (e.g., sensors that output data representative ofmovement in one or more directions, such as accelerometers), pressuresensors (e.g., sensors that output data representative of fluidpressure, such as air pressure in tires of the vehicles, pressures ofoil or other lubricants in gear boxes and/or engines, etc.), fluidsensors (e.g., sensors that output data representative of an oil orother fluid level, or how much fluid, oil or other lubricant is in gearboxes, engines, etc.), positioning sensors (e.g., sensors that outputdata representative of geographic or other locations, such as a globalpositioning system receiver), speed sensors (e.g., sensors that outputdata representative of how rapidly a vehicle is moving, how rapidly awheel and/or axle is rotating, etc.), acoustic sensors (e.g., sensorsthat output data representative of sounds, such as microphones), opticsensors (e.g., sensors that output data representative of images and/orvideos, such as cameras, infrared detectors), electromagnetic sensors(e.g., sensors that obtain and/or output data using electromagneticwaves, such as radio frequency identification interrogators or tags),etc. While the same reference number 116 is used to identify thesensors, the sensors 116 may represent different types of sensors.

The sensors may be operably connected with the gear boxes, tractionmotors, or the like, to monitor fluid levels. In one embodiment, thesensors may include fluid level sensors, such as one or more of the oillevel sensors described in one or more of U.S. patent application Ser.Nos. 14/421,245; 14/866,320; or 14/869,038. Alternatively, the sensorsshown in FIG. 1 may be one or more other types of sensors, such assensors measuring an amount of fuel in a fuel tank, an amount of coolantin a cooling system, etc. The sensors communicate data representative ofthe characteristics being monitored by the sensors (e.g., capacitance ofthe lubricant, an amount of the lubricant, vibrations, location of thevehicle, etc.) to the control system. The control system may use thedata for one or more purposes as described herein. The components of thevehicle system and/or sensor system may be operably connected by one ormore conductive pathways (e.g., cables, wires, buses, etc.) and/orwireless connections to allow for communication between the components.

A controller 118 optionally may be included in the sensor system. Thecontroller can represent hardware circuitry that includes and/or isconnected with one or more processors (e.g., microprocessors, fieldprogrammable gate arrays, integrated circuits, or other electroniclogic-based devices) that communicate with the sensors to receive thedata from the sensors. The controller may be operably connected with thesensors to operate as a gateway for the sensors to communicate senseddata with the control system. The controller may communicate some or allof the data to the control system. The processing of data or othersignals that are provided or output by the sensors as described hereinmay be performed by the controller, by the control system, and/or acombination of the controller and/or control system. In one embodiment,the controller may be disposed off-board of the vehicle and/or thevehicle system to perform the signal processing.

FIG. 2 illustrates one embodiment of one of the propulsion systems 110in the vehicle 104 shown in FIG. 1. The propulsion system includes agear box housing 200 in which one or more gears 202 connect a tractionmotor 204 with the axle 122. The axle 122 is connected with wheels 112on opposite ends of the axle 122, although only a single wheel is shownin FIG. 2. The housing may hold a lubricant, such as oil, forlubricating gears and the like that interconnect a traction motor withan axle of the vehicle. The lubricant may be disposed within a lowerportion of the housing, and the sensor 116 (shown in FIG. 1) may extendinto the housing and at least partially into the lubricant inside thehousing. The sensor can measure one or more characteristics of thelubricant, as described in one or more of U.S. patent application Ser.Nos. 14/421,245; 14/866,320; or 14/869,038. Additionally oralternatively, the same or another sensor may be connected with thepropulsion system to measure vibrations, temperatures, or othercharacteristics of the propulsion system. Optionally, one or more of thesensors may be disposed onboard the vehicle, but not coupled with thepropulsion system.

One or more of the sensors onboard the vehicle may sense vibrations. Forexample, one or more of the sensors may include an accelerometer thatmeasures movements in one or more directions. Such a sensor may bedisposed on the gear box housing, traction motor, or elsewhere tomeasure vibrations. The vibrations may be indicative of speeds ortorques at which the traction motors operate (e.g., with one or moreharmonic frequencies in a frequency domain representation of thevibrations indicating the motor speed), damage to the propulsion system(e.g., with peaks occurring at one or more frequencies in the frequencydomain representation of the vibrations indicating damage to bearings,raceways, etc., of the motors), or the like. In one example, the sensorsmay include one or more of the sensor assemblies described in U.S.Provisional Application No. 62/269,265, filed 18 Dec. 2015, and titled“Vehicle Sensor Assembly And Method,” the entire disclosure of which isincorporated herein by reference.

Optionally, one or more of the sensors onboard the vehicle may sensetemperatures. For example, one or more of the sensors may includethermocouples or other temperature sensitive devices that measuretemperatures of the gears, housing, motor, axles, etc. Such a sensor maybe disposed on the gear box housing, traction motor, or elsewhere tomeasure temperatures. The temperatures may be indicative of damage toone or more components of the propulsion system. For example, elevatedtemperatures of an axle or temperatures of one axle that deviate fromthe temperatures of other axles in the same vehicle may indicate thatthe axle is damaged.

FIG. 3 illustrates a circuit diagram of at least one of the sensors 116shown in FIG. 1 according to one embodiment. The sensor shown in FIG. 3sensor represents one or more of the sensors described in U.S. patentapplication Ser. Nos. 14/421,245; 14/866,320; and/or 14/869,038.Alternatively, the sensor in FIG. 3 may represent another type ofsensor. The sensor includes a housing 444 in which plural circuit boards400, 402 with components connected with the circuit boards are disposed.Several sensing bodies (also referred to as sensors) 404, 412, 414(e.g., “Oil Level Sensor,” “2 g accelerometer,” and “16 g accelerometer”in FIG. 3) represent components that are sensitive to one or morecharacteristics being monitored or measured by the sensor, such as acapacitive element configured to measure the capacitance of a fluid todetermine how much fluid is present, accelerometers configured tomeasure movement, a thermocouple configured to measure temperature, etc.In the illustrated embodiment, the sensor 404 is a capacitive elementconfigured to measure the capacitance of oil to determine how much oilis present and the sensors 412, 414 are accelerometers configured tomeasure movement in one or more different directions.

The sensing elements are operably connected with one or more processors406 that sample the measurements made by the sensing element. Thesensing element may be connected with processor 406 by an electrostaticdischarge (ESD) protection device 408, such as a conductor having adielectric and/or electromagnetic shield disposed around the conductor.The processor is connected with several other components, including acomputer-readable memory 410 where the sampled measurements can be atleast temporarily stored. A microcontroller 416 is operably connectedwith the processor and memory to control the transfer of data (e.g.,measurements) to one or more other components. An onboard power source418, such as a battery, can supply electric current to power thecomponents of the sensor via a filter 420 (“Filter Capacitance Bank” inFIG. 3) and a switch 422 (“Power switching status indicator” in FIG. 3)that controls conduction of the current from the power source.

Communication interfaces 424, 426 represent connections between thecircuit boards that allow communication of data between the boards. Thecommunication interfaces can represent conductive busses, wires, or thelike. A connector 428 (“Programming Connector”) can couple with one ormore other devices in order to communicate with the components of thesensor shown in FIG. 3. The data sampled by the sensor can becommunicated out of the sensor via one or more divergent communicationpaths. One path wirelessly communicates the data to the controller 118and includes a first transceiver 430, such as a 2.45 GHz transceiver oranother type of transceiver. The first transceiver is operably connectedwith a first antenna 434, such as a 2.4 GHz patch antenna or anothertype of antenna, by an ESD protection device 432 (“Matching network ESDprotection” in FIG. 3). The sensor 116 may wirelessly communicate thesensed data or characteristics to the controller 118 using the antenna434 and transceiver 430. In another communication path, a radiofrequency identification (RFID) transponder 436 (“IDS SL900 UHF RFID” inFIG. 3) is operably connected with the communication interface 426.Another ESD protection device 438 may be disposed between thetransponder 436 and an antenna 440 (“915 MHz Patch Antenna” in FIG. 3).The transponder 436 and antenna 440 may be used to wirelesslycommunicate the data or measurements obtained by the sensor 116 to aninterrogator device 442, such as an RFID reader. Alternatively, theantenna 440 may wirelessly communicate the data in another manner and/orto another device.

In one embodiment, the control system may use the vibrations measured bythe sensors to determine health or damage states of the propulsionsystems and/or to predict when the propulsion systems will fail orrequire repair or replacement. These sensors may include or representhardware circuitry that includes and/or is connected with one or moreprocessor (e.g., microprocessors, field programmable gate arrays,integrated circuits, or other electronic logic-based devices) thatsample and process the measured vibrations for communication from thesensors to the controller and/or control system.

The propulsion systems include gears that mesh with each other and thatalso may vibrate during operation. The vibrations of the meshing gearsmay be detected by the sensors and communicated to the control system asmeasured vibrations of the propulsion system. In order to determine thehealth of or damage to a propulsion system (and/or to predict failure ofa propulsion system), the controller and/or control system may removethe vibrations of the meshing gears from the vibrations measured by thesensors before performing analysis of the vibrations (e.g., to determinethe health/damage state or predict failure of the propulsion system).

FIG. 4 illustrates a frequency signature 300 of a propulsion systemaccording to one example. The frequency signature is a frequency domainrepresentation of vibrations of the propulsion system as measured by oneor more sensors. The frequency signature is shown alongside a horizontalaxis 302 representative of frequencies of the vibrations and a verticalaxis 304 representative of magnitudes of the vibrations. The frequencysignature includes several peaks 306, 308, 310, 312, 314. Thefrequencies at which the peaks occur may represent operation and/orhealth of the propulsion system. For example, one peak may occur at afrequency indicative of the speed at which the traction motor of thepropulsion system operates, another peak may occur at a frequencyindicative of damage to a raceway, bearings, or the like, of thepropulsion system, or other operations of the propulsion system.

In one embodiment, one or more of the peaks may represent a frequency atwhich meshed gears in the propulsion system are vibrating. For example,one peak may represent the speed at which the motor is operating, butthe other peaks may represent vibrations of the gear mesh and/or damageto the propulsion system. In order to prevent the control system and/orcontroller from incorrectly identifying one or more of the gear meshpeaks being indicative of motor speed or health/damage state of thepropulsion system, the controller and/or control system may receivemovement signals and/or vibration signals indicative of movements and/orvibrations of the gears from one or more sensors, filter out one or moreportions of the vibration signals and/or movement signals from thefrequency signature that represent the vibrations or movements of thegears. Another method to determine wheel speed is directly from thevibration sensor itself for cases where the drive train exhibitsvibrational spectra indicative of wheel speed such as is the case when agear mesh is coupled to the wheel speed. For example, a frequency domainspectrum of measured vibrations may include one or more peaks. Thefrequency or frequencies at which the one or more peaks occur may berepresentative of the wheel speed. Larger frequencies may representfaster wheel speeds and smaller frequencies may represent slower wheelspeeds. The wheels speeds may be determined directly from the vibrationspectrum or spectra detected by the sensors.

The mesh vibrations may include a fundamental component associated witha rate at which teeth of the gears mesh with each other. Because thegears are rotated by the motor to rotate the axle, the rate at which thegear teeth mesh (e.g., the gear mesh rate) may be proportional to theaxle speed, or the speed at which the axle rotates. The magnitude of thegear mesh vibrations may dominate the magnitudes of other vibrations ofthe propulsion system in conditions where the propulsion system is in ahealthy state (e.g., not damaged) and in a damaged state. The use offixed bandwidth analog or digital low pass filters to reject or removethe vibration signals indicative of mesh-related vibrations from thevibrations that are used to determine motor speed and/or thehealth/damage state of the propulsion system. But, because thefrequencies at which the gear mesh vibrations occur may change (e.g.,with changing motor speed), the fixed bandwidth filters mayinadvertently remove frequencies and/or peaks that are notrepresentative of gear mesh vibrations.

In one embodiment, the sensor (e.g., the processor 406), the controller,and/or control system may receive the vibrations measured by the sensorsand apply a speed-proportional bandwidth filter to the vibration signalsindicative of measured vibrations to remove some or all vibrationssignals indicative of gear mesh vibrations from the vibration signals.The bandwidth filter may remove all vibration signals indicative ofvibration frequencies appearing within the bandwidth or frequency rangeof the filter, which changes with changing axle speeds. For faster axlespeeds, the bandwidth of the filter may increase so that a larger rangeof vibration signals indicative of a larger range of vibrationfrequencies are removed from the measured vibrations. For slower axlespeeds, the bandwidth of the filter may decrease so that a smaller rangeof the vibration signals representative of a smaller range of vibrationfrequencies are removed. The axle speed information needed to programthe filter can be provided to the sensor, the controller, and/or thecontrol system wirelessly and/or can be measured directly by the sensor,controller, and/or control system (e.g., by identifying the largest peakin the frequency signature of the vibrations and determining the axlespeed from that peak). Additionally or alternatively, the sensor,controller, and/or control system may apply a programmable digitalfilter to the vibration signals to remove the signals representative ofgear mesh vibrations. This can be similar to using thespeed-proportional bandwidth described above, with one difference beingthat the filter is implemented by a digital signal processor (DSP) orother processor to reject the gear mesh frequency or frequencies.

Additionally or alternatively, the sensor (e.g., the processor 406) mayapply a fast Fourier transform (FFT) or discrete Fourier transform (DFT)to the vibration signals and communicate the transformed vibrationsignals to one or more components disposed off-board the sensor, such asthe controller, the control system, the interrogator device 442, and/ora controller disposed off-board the vehicle and/or vehicle system. Thecomponent that receives the transformed vibration signals may beprovided with the speed at which the vehicle is moving (e.g., from oneor more of the sensors that represents a tachometer or from anothersource). This speed can be used to determine where the gear meshfrequencies are expected to be found, such as by examining harmonicfrequencies of a fundamental harmonic frequency in the transformedvibration signals. The harmonic frequencies may represent gear meshfrequencies while the fundamental frequency can represent the speed ofthe vehicle. Other frequencies can represent the health/damage state ofthe propulsion system.

Some of the sensors may include processors 406 that sample thevibrations, but are unable to perform spectral analysis of the measuredvibrations. The processors in the sensors may lack the ability toperform full spectral analyses of the vibration signals due to therelatively small form factors, cost limitations, or the like, of thesensors. These sensors may measure the vibrations in another manner,such as by measuring a quadratic mean or root-mean-square (RMS) of thesampled vibrations. A sensor can measure and calculate the RMS ofvibration signals associated with multiple, different axes, such as thesignals indicative of vibrations measured along three orthogonal axes(e.g., along the x-, y-, and z-axes). The sensor can sample thevibrations along the three different axes and communicate the vibrationsignals indicative of the measured vibrations along three differentcommunication channels to one or more processors.

The accelerometer portion of the sensor may be capacitively coupled(e.g., coupled via capacitance) with the one or more processors, such asby an AC coupling. This coupling provides a high pass filter to thesampled vibrations along the different axes. The sampled vibrationsalong any or all of the different may be accumulated over a designatedtime period, such as 200 milliseconds (or another time period). Forexample, a vibration sampled along any axis during this time period maybe squared, and an average of the squared samples acquired during thistime period may be averaged. The square root of the average of thesquared samples may be calculated for the time period. The value of thesquare root of the average of the squared samples may be used torepresent the vibration measured by the sensor for the time period.Calculating the single vibration value for the time period can reducethe amount of data or information being handled by the sensor, and canreduce the processing needed to examine the vibrations measured by thesensor.

As described above, the sensor may use an onboard power source, such asone or more batteries, to power the components of the sensor. Becausebatteries are limited energy resources, the amount of energy that thesensor can use to measure, process, store, and/or communicate the datathat is accumulated can be limited. The sensor may use a samplingstrategy that employs a low duty cycle for measuring characteristics.Such a duty cycle can include a dominant sleep mode for the processorand other electronic components of the sensor, which the componentsbeing inactive during a majority of the time but periodically activatingto record characteristics (e.g., temperature and/or vibration levels).

Due to the amount of data collected by the sensor and the processingcomplexity involved in examining the data to determine relevantinformation from the data, some sensors may the data off-board toanother component for processing). The collection of data and subsequentcommunication of data can require seconds of data capture followed byseveral seconds of data communication. This process can significantlyimpact the lifetime of a battery within the sensor. By processing thedata locally within the sensor (such as the processor 406 calculatingRMS of vibration measurements, determining FFT or DFT of the vibrationmeasurements, or the like), the communication times are significantlyreduced. For example, instead of communicating a large amount of dataover a longer time period, a smaller amount of processed data (e.g., theRMS values, the FFT or DFT of the sensed data, etc.) can be communicatedout of the sensor over a shorter time period. The time required forcommunication (and for the battery to power the components thatwirelessly communicate information from the sensor) may be reduced fromseveral seconds to a fraction of a second. This can extend the lifetimeof the battery from months to several years or longer.

Optionally, the system described herein may abort or not beginprocessing of the vibration or movement signals indicative of measuredvibrations by one or more sensors if there are low levels of vibrationor no vibration measured by the one or more sensors. For example, if asensor measures no vibration or vibrations that are less than adesignated threshold (e.g., less than 5%, less than 3%, less than 1%, orthe like, of previously measured vibrations), the system may not examineor process the vibrations. This can save battery energy by notprocessing data that represents little, if any, vibrations.

Additionally or alternatively, the sensor may employ different wirelesscommunication techniques to communicate data and reduce the amount ofpower consumption needed to power the sensor (e.g., relative to sensorsthat rely on a single type of wireless communication). As describedabove in connection with FIG. 3, the sensor may have plural differentways to communicate data. One technique for communicating data may bevia a wireless channel or link using the antenna 434. In one embodiment,this communication may involve communicating data on an IEEE 802.15.4wireless link, which may be a 2.5 GHz link. Another technique forcommunicating the data may be via a lower power RFID link establishedusing the antenna 440, such as a 915 MHz link. The link establishedusing the antenna 434 may be a primary mode of communication with arange of about 200 feet or another distance, such as a distance that islonger than the longest dimension of the vehicle on which the sensor isdisposed.

The sensor may communicate data on the primary link on a predeterminedschedule when the sensor wakes up or activates from a sleeping orinactive state. The time interval for this schedule may be customizable.As one example, this interval may be 1 hour or more to conserve batterypower. In one embodiment, the processor may be programmed to prevent thesensor from activating and communicating via the primary communicationlink during the interval (e.g., between times at which the sensor isactivated). In order to allow the data to be obtained from the sensorduring the inactive time periods of the sensor, the secondarycommunication link provided by the antenna 440 may provide a power,radio frequency (RF) communication link using a 915 MHz RFID antenna.

This secondary link can provide another way to communicate with thesensor during time periods that the sensor is not actively communicatingusing the primary communication link. The range of the secondary linkmay be limited, such as to a distance that is smaller than the longestdimension of the vehicle on which the sensor is disposed. For example,the range of the secondary link may be 15 feet or less. The antenna 440used to establish the secondary link may be a passive antenna that isactivated by interrogation of the antenna 440 with electromagnetic wavesgenerated by the reader 442. The communication link activates theprocessor 406 using the externally excited antenna 440 and correspondingcircuitry that communication with the sensor is possible even duringtimes that the sensor is inactive. This allows for near instantaneousreadings of data read by the sensor. In one example, the antenna 440 mayreceive signals that re-flash or update the firmware of the sensor, thatalter or reset the communication parameters of the other communicationlink (e.g., by changing the activation interval), or the like.

FIG. 5 illustrates a flowchart of one embodiment of a method 500 forsensing, processing, and/or communicating data representative ofcharacteristics of a powered system. The method 500 may be performed byone or more embodiments of the sensor system described herein. Themethod 500 may be used to sense, process, and/or communicate datarepresentative of powered systems such as vehicles, but not allembodiments are limited to vehicles. At 502, one or more characteristicsof the powered system are sensed using a sensor. For example,vibrations, temperatures, fluid levels, or the like, may be sensed. At504, a determination is made as to whether signals indicative of thecharacteristics that are sensed are to be filtered. For example, somesignals may represent characteristics of interest (e.g., characteristicsthat can be examined in order to determine a health or failure state ofthe powered system) and other signals may not represent characteristicsof interest (e.g., characteristics that, if examined, are notrepresentative of the health or failure state of the powered system).

If any of the signals are to be filtered, then flow of the method 500can proceed toward 504. At 504, signals indicative of one or more of thecharacteristics are filtered. For example, movement or vibration signalsindicative of vibrations that are gear mesh vibrations may be removedfrom the signals representative of measured vibrations of a propulsionsystem. The movement or vibration signals may be removed using a filter,such as a filter having a bandwidth that varies based on an operatingspeed of the propulsion system or motor, a digital filter implemented bya processor, etc. If the characteristics are not to be filtered, thenflow of the method 500 may proceed from 502 toward 506.

At 506, the signals indicative of the characteristics optionally can beprocessed prior to communicating the signals outside of the sensor. Forexample, in order to distinguish between characteristics of interest(e.g., vibrations of a traction motor) and characteristics that are notof interest (e.g., gear mesh vibrations), the sensor may determine anFFT or DFT of the signals indicative of the characteristics that aremeasured and communicate the FFT or DFT to an off-board location, wherethe FFT or DFT is examined. As another example, the sensor may calculatea statistical measure of the signals that are indicative of thecharacteristics of interest, such as an average, root mean square, orthe like, for communication to an off-board location. Thispre-communication processing can reduce the amount of time needed tocommunicate the information out of the sensor, which can extend thebattery life of the sensor.

At 508, a determination is made as to whether an activation time hasbeen reached. An activation time can occur at regular intervals. Duringthe activation time, the sensor may activate, measure characteristics,and/or communicate the signals indicative of the characteristics orprocessed characteristics out of the sensor. If an activation time hasbeen reached, then flow of the method 500 may proceed toward 510. At510, the signals indicative of the information that has been sensed(e.g., the characteristics and/or processed characteristics) arecommunicated out of the sensor, such as via the primary communicationlink of the sensor described above.

If the activation time has not been reached, then the method 500 canproceed from 508 toward 512. For example, the current time may bebetween activation times, so the sensor does not communicate the signalsindicative of the sensed information using the primary communicationlink. At 512, a determination is made as to whether the sensor has beeninterrogated for the sensed information between the activation times.For example, a determination may be made as to whether an RFID device isemitting electromagnetic waves to activate a secondary communicationlink of the sensor. If the sensor is being interrogated, then flow ofthe method 500 can proceed toward 514. Otherwise, the method 500 mayproceed toward 516. At 514, the signals indicative of the sensedinformation are communicated out of the sensor via the secondarycommunication link. For example, the characteristics and/or processedcharacteristics can be wirelessly communicated via a RF signal by way ofan RF connection. At 516, the signals indicative of the sensedinformation are communicated via the primary communication link during asubsequent activation time. For example, if the current time is not anactivation time, then the sensor may wait until the next activation timeor until the sensor is interrogated to communicate the characteristicsor processed characteristics.

In one embodiment, a sensor assembly includes one or more accelerometersconfigured to generate movement signals indicative of sensed movement ofa powered system in one or more directions, a fluid level sensorconfigured to generate fluid level signals indicative of a sensed amountof fluid in the powered system, and one or more processors configured toreceive the movement signals and the fluid level signals from the one ormore accelerometers and the fluid level sensor. The one or moreprocessors also are configured to one or more of filter at least some ofthe movement signals based on a speed at which the powered systemoperates or calculate one or more of statistical measure, a fast Fouriertransform (FFT), or a discrete Fourier transform (DFT) of the movementsignals. The assembly also includes a first antenna configured towirelessly communicate the one or more of the movement signals, theamount of fluid, the statistical measure, the FFT, or the DFT to aremote location.

Optionally, the assembly also can include a housing in which the one ormore accelerometers, the fluid level sensor, the one or more processors,and the first antenna are disposed.

Optionally, the one or more processors are configured to filter themovement signals with a filter having a bandwidth that increases forfaster speeds of a motor of the powered system and that decreases forslower speeds of the motor.

Optionally, the one or more processors are configured to calculate thestatistical measure of the movement signals as a combination ofmovements of a propulsion system of the powered system in multiple,different directions.

Optionally, the one or more processors are configured to calculate thestatistical measure as a root mean square of the movement signals of thepropulsion system in the multiple, different directions over a samplingperiod.

Optionally, the first antenna is configured to wirelessly communicatethe one or more of the movement signals, the amount of fluid, thestatistical measure, the FFT, or the DFT to the remote location atregular intervals. The assembly optionally also can include a secondantenna configured to wirelessly communicate the one or more of themovement signals, the amount of fluid, the statistical measure, the FFT,or the DFT to the remote location responsive to receipt of aninterrogation signal from an external device.

Optionally, the first antenna is configured to communicate the one ormore of the movement signals, the amount of fluid, the statisticalmeasure, the FFT, or the DFT over a first communication link and thesecond antenna is configured to communicate the one or more of themovement signals, the amount of fluid, the statistical measure, the FFT,or the DFT over a different, second communication link, wherein thefirst communication link is a higher power and longer rangecommunication link than the second communication link.

In one embodiment, a system includes a sensor configured to generatevibration signals indicative of senses vibrations of a vehicle, and oneor more processors configured to one or more of: filter at least some ofthe vibration signals based on a speed at which a motor of the vehicleoperates and communicate the vibration signals that are not filtered outof the sensor, or calculate one or more of statistical measure, a fastFourier transform (FFT), or a discrete Fourier transform (DFT) of thevibration signals and communicate the one or more of the statisticalmeasure, the FFT, or DFT out of the sensor.

Optionally, one or more processors are configured to filter the at leastsome of the vibration signals with a filter having a bandwidth thatincreases for faster speeds of the motor and that decreases for slowerspeeds of the motor.

Optionally, the one or more processors are configured to calculate thestatistical measure of the vibration signals as a combination ofmovements of a propulsion system of the vehicle in multiple, differentdirections.

Optionally, the one or more processors are configured to calculate thestatistical measure as a root mean square of the vibration signals ofthe propulsion system of the vehicle in the multiple, differentdirections over a sampling period.

Optionally, the one or more processors are configured to communicate oneor more of the vibration signals, the statistical measure, the FFT, orthe DFT at regular intervals via a first wireless communication link andto communicate the one or more of the vibration signals, the statisticalmeasure, the FFT, or the DFT responsive to receipt of an interrogationsignal from an external device via a different, second wirelesscommunication link.

Optionally, the first wireless communication link is a higher power andlonger range communication link than the second wireless communicationlink.

Optionally, the system also may include a transceiver and a firstantenna configured to communicate the one or more of the vibrationsignals, the statistical measure, the FFT, or the DFT at the regularintervals over the first communication link at a designated frequency.

In one embodiment, a method includes generating vibration signalsrepresentative of sensed vibrations of a vehicle using a sensor, and oneor more of: filtering at least some of the vibration signals that aresensed based on a speed at which a motor and wheels of the vehicleoperates and communicating the vibration signals that are not filteredout of the sensor, or calculating one or more of statistical measure, afast Fourier transform (FFT), or a discrete Fourier transform (DFT) ofthe vibration signals and communicating the one or more of thestatistical measure, the FFT, or DFT out of the sensor.

Optionally, the method includes aborting the one or more of filtering orcalculating responsive to the vibrations that are represented by thevibration signals being less than a designated, non-zero threshold.

Optionally, the method also can include determining the speed at whichthe wheels rotate based on the vibration signals.

Optionally, the method includes filtering the at least some of thevibration signals with a filter having a bandwidth that increases forfaster speeds of the motor and that decreases for slower speeds of themotor.

Optionally, the method includes calculating the statistical measure ofthe vibration signals as a combination of movements of a propulsionsystem of the vehicle in multiple, different directions.

Optionally, the statistical measure is calculated as a root mean squareof the vibration signals of the propulsion system of the vehicle in themultiple, different directions over a sampling period.

It is to be understood that the above description is intended to beillustrative, and not restrictive. For example, the above-describedembodiments (and/or aspects thereof) may be used in combination witheach other. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the inventivesubject matter without departing from its scope. While the dimensionsand types of materials described herein are intended to define theparameters of the inventive subject matter, they are by no meanslimiting and are exemplary embodiments. Many other embodiments will beapparent to those of ordinary skill in the art upon reviewing the abovedescription. The scope of the inventive subject matter should,therefore, be determined with reference to the appended clauses, alongwith the full scope of equivalents to which such clauses are entitled.In the appended clauses, the terms “including” and “in which” are usedas the plain-English equivalents of the respective terms “comprising”and “wherein.” Moreover, in the following clauses, the terms “first,”“second,” and “third,” etc. are used merely as labels, and are notintended to impose numerical requirements on their objects. Further, thelimitations of the following clauses are not written inmeans-plus-function format and are not intended to be interpreted basedon 35 U. S.C. § 112(f), unless and until such clause limitationsexpressly use the phrase “means for” followed by a statement of functionvoid of further structure.

This written description uses examples to disclose several embodimentsof the inventive subject matter and also to enable any person ofordinary skill in the art to practice the embodiments of the inventivesubject matter, including making and using any devices or systems andperforming any incorporated methods. The patentable scope of theinventive subject matter is defined by the clauses, and may includeother examples that occur to those of ordinary skill in the art. Suchother examples are intended to be within the scope of the clauses ifthey have structural elements that do not differ from the literallanguage of the clauses, or if they include equivalent structuralelements with insubstantial differences from the literal languages ofthe clauses.

The foregoing description of certain embodiments of the inventivesubject matter will be better understood when read in conjunction withthe appended drawings. To the extent that the figures illustratediagrams of the functional blocks of various embodiments, the functionalblocks are not necessarily indicative of the division between hardwarecircuitry. Thus, for example, one or more of the functional blocks (forexample, processors or memories) may be implemented in a single piece ofhardware (for example, a general purpose signal processor,microcontroller, random access memory, hard disk, and the like).Similarly, the programs may be stand-alone programs, may be incorporatedas subroutines in an operating system, may be functions in an installedsoftware package, and the like. The various embodiments are not limitedto the arrangements and instrumentality shown in the drawings.

As used herein, an element or step recited in the singular and proceededwith the word “a” or “an” should be understood as not excluding pluralof said elements or steps, unless such exclusion is explicitly stated.Furthermore, references to “one embodiment” of the inventive subjectmatter are not intended to be interpreted as excluding the existence ofadditional embodiments that also incorporate the recited features.Moreover, unless explicitly stated to the contrary, embodiments“comprising,” “including,” or “having” an element or a plurality ofelements having a particular property may include additional suchelements not having that property.

Since certain changes may be made in the above-described systems andmethods for communicating data in a vehicle consist, without departingfrom the spirit and scope of the inventive subject matter hereininvolved, it is intended that all of the subject matter of the abovedescription or shown in the accompanying drawings shall be interpretedmerely as examples illustrating the inventive concept herein and shallnot be construed as limiting the inventive subject matter.

What is claimed is:
 1. A method comprising: generating movement signalsindicative of sensed movement of a powered system in one or moredirections with one or more accelerometers of a sensor assembly;generating fluid level signals indicative of a sensed amount of fluid inthe powered system with a fluid level sensor of the sensor assembly;receiving the movement signals from the one or more accelerometers andthe fluid level signals from the fluid level sensor using one or moreprocessors of the sensor assembly; filtering at least some of themovement signals based on a speed at which the powered system operateswith the one or more processors; and wirelessly communicating one ormore of the movement signals or the amount of fluid to a remote locationwith a first antenna of the sensor assembly.
 2. The method of claim 1,wherein the at least some of the movement signals are filtered using afilter having a bandwidth that changes based on the speed at which thepowered system operates.
 3. The method of claim 2, wherein the bandwidthof the filter increases for faster speeds of a motor of the poweredsystem and decreases for slower speeds of the motor.
 4. The method ofclaim 1, wherein the movement signals represent a combination ofmovements of a propulsion system of the powered system in multiple,different directions.
 5. The method of claim 1, further comprising:calculating a root mean square of the movement signals over a samplingperiod with the one or more processors.
 6. The method of claim 1,further comprising: wirelessly communicating the one or more of themovement signals or the amount of fluid with the first antenna to theremote location at regular intervals and wirelessly communicating theone or more of the movement signals or the amount of fluid with a secondantenna to the remote location responsive to receipt of an interrogationsignal from an external device.
 7. The method of claim 6, wherein theone or more of the movement signals or the amount of fluid arecommunicated with the first antenna via a first communication link andthe one or more of the movement signals or the amount of fluid arecommunicated with the second antenna via a different, secondcommunication link.
 8. The method of claim 7, wherein the firstcommunication link is a higher power and longer range communication linkthan the second communication link.
 9. A method comprising: with one ormore accelerometers of a sensor assembly, generating movement signalsindicative of sensed movement of a powered system in one or moredirections; with a fluid level sensor of the sensor assembly, generatingfluid level signals indicative of a sensed amount of fluid in thepowered system; with one or more processors of the sensor assembly,receiving the movement signals and the fluid level signals from the oneor more accelerometers and the fluid level sensor; one or more of (a)filtering at least some of the movement signals with a filter having abandwidth that increases for faster speeds of a motor of the poweredsystem and that decreases for slower speeds of the motor or (b)calculating one or more of a fast Fourier transform (FFT) or a discreteFourier transform (DFT) of the movement signals; and with a firstantenna of the sensor assembly, wirelessly communicating one or more ofthe movement signals, the amount of fluid, the FFT, or the DFT to aremote location.
 10. The method of claim 9, wherein the method includesfiltering the at least some of the movement signals with the filterhaving the bandwidth that increases for the faster speeds of the motorof the powered system and that decreases for the slower speeds of themotor.
 11. The method of claim 9, wherein the method includescalculating the one or more of FFT or the DFT of the movement signals.12. The method of claim 9, wherein the movement signals represent acombination of movements of a propulsion system of the powered system inmultiple, different directions.
 13. The method of claim 12, furthercomprising: calculating a root mean square of the movement signals ofthe propulsion system in the multiple, different directions over asampling period with the one or more processors.
 14. The method of claim9, further comprising: wirelessly communicating the one or more of themovement signals, the amount of fluid, the FFT, or the DFT with thefirst antenna to the remote location at regular intervals and wirelesslycommunicating the one or more of the movement signals, the amount offluid, the FFT, or the DFT with a second antenna to the remote locationresponsive to receipt of an interrogation signal from an externaldevice.
 15. The method of claim 14, wherein the one or more of themovement signals, the amount of fluid, the FFT, or the DFT arecommunicated with the first antenna via a first communication link andthe one or more of the movement signals, the amount of fluid, the FFT,or the DFT are communicated with the second antenna via a different,second communication link.
 16. The method of claim 15, wherein the firstcommunication link is a higher power and longer range communication linkthan the second communication link.
 17. A method comprising: with one ormore accelerometers of a sensor assembly, generating movement signalsindicative of sensed movement of a powered system in one or moredirections; with a fluid level sensor of the sensor assembly, generatingfluid level signals indicative of a sensed amount of fluid in thepowered system; with one or more processors of the sensor assembly,receiving the movement signals and the fluid level signals from the oneor more accelerometers and the fluid level sensor; one or more of (a)filtering at least some of the movement signals based on a speed atwhich the powered system operates or (b) calculating one or more of afast Fourier transform (FFT) or a discrete Fourier transform (DFT) ofthe movement signals; and with the first antenna, wirelesslycommunicating one or more of the movement signals, the amount of fluid,the FFT, or the DFT to the remote location at predetermined intervals,and, with a second antenna, wirelessly communicating one or more of themovement signals, the amount of fluid, the FFT, or the DFT to the remotelocation responsive to receipt of an interrogation signal from anexternal device.
 18. The method of claim 17, wherein the movementsignals represent a combination of movements of a propulsion system ofthe powered system in multiple, different directions.
 19. The method ofclaim 18, further comprising: calculating a root mean square of themovement signals of the propulsion system in the multiple, differentdirections over a sampling period with the one or more processors. 20.The method of claim 8, wherein the one or more of the movement signals,the amount of fluid, the FFT, or the DFT are communicated to the remotelocation via a higher power and longer range communication link and theone or more of the movement signals, the amount of fluid, the FFT, orthe DFT are communicated to the remote location via a lower power andshorter range communication link.